Wireless communication networks are widely deployed to provide various communication services such as telephony, video, data, messaging, broadcasts, and so on. Such networks, which are usually multiple access networks, support communications for multiple users by sharing the available network resources. One example of such a network is the UMTS Terrestrial Radio Access Network (UTRAN). The UTRAN is the radio access network (RAN) defined as a part of the Universal Mobile Telecommunications System (UMTS), a third generation (3G) mobile phone technology supported by the 3rd Generation Partnership Project (3GPP).
Generally, wireless user equipment (UE) (also referred to as mobile station (MS), mobile terminal (MT), access terminal (AT), etc. in various literature) configured for UMTS uses a Universal Integrated Circuit Card (UICC) (generally referred to as a SIM card) to store subscriber identity and for other security and authentication purposes. More recently, some UEs have two or more UICCs or SIM cards such that the user of the device can simultaneously engage in a voice call and/or data call on two or more cellular subscriptions. These subscriptions might be on the same network or different networks.
A UE with multiple SIM cards is generally referred to as a multi-SIM device. Some multi-SIM UEs share radio frequency (RF) resources (e.g., modem, transceiver, etc.) for accessing multiple subscriptions simultaneously. One category of multi-SIM devices is called a dual-SIM dual active (DSDA) device. A DSDA device can be simultaneously active on two subscriptions in a traffic mode, and may accordingly exhibit coexistence issues.